Qualitative description of the spectrum of a linear molecule in an arbitrary electronic state

The most general qualitative method for constructing effective operators of physical quantities is considered for describing the spectrum of a linear molecule in both the nondegenerate and the degenerate electronic state. The method is based on using the concept of the coordinate spin of a molecule within the framework of the symmetry-group chain approach for models arising in the perturbative analytic solution of the stationary state problem of a molecule. 8 refs., 1 fig.